// 根据设计稿1920宽度进行自适应
(function (doc,win){
    var docEl = doc.documentElement,
    resizeEvt = "orientationchange" in window ? "orientationchange" :"resize",
    recalc = function() {
        var clientWidth = docEl.clientWidth;
        if(!clientWidth) return;
        if(clientWidth > 1920) {
            clientWidth = 1920   //1rem = 100px
            docEl.style.fontSize = "100px"
        }
        docEl.style.fontSize = 100 * (clientWidth / 1920) + "px"
    };
    win.addEventListener(resizeEvt,recalc,true);
    doc.addEventListener("DOMContentLoaded",recalc,false)
})(document,window)